Not to mention, vest is best—specifically the Patagonia Women's Down Sweater Vest. Designed to maintain core warmth, the Down Sweater Vest features high-loft, 800-fill Traceable Down insulation, which traps that hard-earned heat and promotes effortless temperature regulation—without making you feel as though you're a tire-toting inanimate object. Additionally, the Traceable Down is certified by NSF (an independent third party) and is derived from geese that are never force-fed or live-plucked, meaning you can feel good about feeling good and cozy.